Why can't 1 gear factory supply 10 red science factories?

[MalcolmCooks]

recipe time for iron gears is 0.5 seconds for 1 iron gear. The grey assembly machines have a crafting speed of 0.5, so 1 iron gear factory should produce 1 iron gear per second.
Likewise, red sceince packs take 5 seconds and consume 1 iron gear, so 1 red science factory should consume 0.1 iron gears per second.
So it follows that you should be able to supply 10 red science pack factories with 1 iron gear factory. But, practical experiments show that you can only supply up to 8, even if you let the supply belt become saturated before you start the red science pack factories.

Why?

[eladmir]

What kind of inserters are you using for your iron gear factory? remember that you need 2 iron plates to make 1 gear. the yellow inserter speed is only 0.84 turns per second. this will not be sufficient to keep a iron gear wheel factory saturated. you need two yellow or a blue. Also I would wanna check if you have enough power. this can significantly reduce your performance and saturation

[MalcolmCooks]

the yellow inserter speed is only 0.84 turns per second.

Wow, there we go. I assumed yellow inserter could move 1 item per second and blue inserter was 2 items per second from what I had measured approximately. I had a yellow inserter taking the gears out of the factory which was slowing it down just slightly enough to not be noticeable

[Xterminator]

the yellow inserter speed is only 0.84 turns per second.

Wow, there we go. I assumed yellow inserter could move 1 item per second and blue inserter was 2 items per second from what I had measured approximately. I had a yellow inserter taking the gears out of the factory which was slowing it down just slightly enough to not be noticeable

Yeah it can be deceiving a lot of the time. Mos my bottlenecks come from a lack of Insertion or exporting speed. Definitely worth checking and watching the assembler work for a few seconds to make sure it isn't being allowed down by anything.

[zytukin]

Definitely have to spend some time watching factories to make sure they are working efficiently.
May seem silly, but it doesn't hurt to spend 5-10 seconds watching every assembler/smelter you build to see if it is getting supplies fast enough and to see if the goods that it produces are being removed as fast as it is producing them.

In the case of rows of buildings making the same thing, generally only need to watch the buildings at the ends of the supply and removal conveyors. Make sure the last building being supplied is getting all the supplies it needs, and make sure the last building that the removal conveyor visits can place it's items on the conveyor as fast as it makes them.

[GewaltSam]

I know the numbers are not exact, but out of experience: If you use a T2 factory without modules, and you need to get 1 part in there for a 0.5 seconds production cycle, you need one blue inserter. Everything that needs even more stuff, you'll need more inserters (like iron gears: two iron bars every 0.5 seconds, so I would take two blues). A yellow inserter is roughly half as fast, so you can calculate one part transported per second. So, for example, if you need 5 parts in an assembler, but the production time is 8 seconds, a yellow one can do all that and still got some time. If you need 10 parts from a belt every two seconds, that's 2.5 parts every 0.5 seconds, so you should opt for 2-3 inserters (because you would need about 2.5 inserters, mathematically).

In the field, you can also open the assembly GUI and watch the assembly progress bar as well as your inserters outside. If the bar halts between production cycles, but one of your inserters is working 100% of the time, it's slowing down your assembly and you need more inserters. If the assembly is able to produce one part after another, you're fine. Also, make sure there's enough material coming through to that assembly in the first place. All the fastest inserters won't help if they got nothing to grab.

After all, it's a mix of theory as well as practical observation. Don't go too crazy with numbers and theoretical speeds; while they are 100% correct and predictable in the simulation if you use the right numbers, it's not that easy to calculate everything before you start building, anyway. Remember that different assemblies have different speeds, modules change the speed also, and so on and so forth. You can calculate it all the way you want, just to find out later that you need an extra inserter anyway because there's some speed boost/bump in your system you haven't considered.

In the end, think about how it *should* look (estimates/guesstimates work a lot better here than exact calculations, in my opinion. Think Murphy's Law: it gets always bigger and takes longer than planned), then build it, then watch it and see how it's working. Simply observing which parts are working all the time and which stand still a lot tells you more about the right inserters/belts/etc. to use than every calculation where you forgot a small detail. That's my experience after several hundred hours with this game. Oh, and that's not saying that calculations can't give you a good idea of what you're doing before starting

[Griffon0129]

This website (link below) has already done all the numbers for you and says how many of each machine down to the furnaces and ores needed for that item then you can even say how many items per second, minute, or hour you want made (also has some mod support).
http://factorio.rotol.me/pack/base-f11/factoratio/

[BlakeMW]

GewaltSam has already said most what I wanted to, I'll just add the exact inserter ratios:

Inserts per second (as of 0.12.30)
Fast: 2.31 (26 ticks/insert)
Long: 1.15 (52 ticks/insert)
Basic: 0.83 (72 ticks/insert)

2 Long Arm Inserters are exactly as fast as 1 Fast Insterter.

There are no precise ratios for Basic Inserters, but approximately 2.8 Basic Inserters = 2 Long Arm Inserters = 1 Fast Inserter, you can remember it as 3:2:1 and it'll be close enough for all practical purposes.

[OkariDraconis]

Likewise, red sceince packs take 5 seconds and consume 1 iron gear, so 1 red science factory should consume 0.1 iron gears per second.

Your Math is off.
1 iron gear per 5 seconds = 0.2 gears per second.
1/5 = 0.2

A grey Factory produces 1 gear per Second
So you need 2 Grey Gear Factories, to keep up with 10 science buildings.
Yellow arms should keep up with grey factory for gears I believe.

[eladmir]

Actually his math is correct, the production speed of gray factories are 0.5 thus you need 0.1 gear per sec and not 0.2

Your Math is off.
1 iron gear per 5 seconds = 0.2 gears per second.
1/5 = 0.2

A grey Factory produces 1 gear per Second
So you need 2 Grey Gear Factories, to keep up with 10 science buildings.
Yellow arms should keep up with grey factory for gears I believe.

Edit: Poor language